Ungumming raw silk.



*' UNITED STATES Pn rENT OFFICE.

' PETER SCHMl-D. OF BASEL, SWITZERLAND.

U'NGUIMIMING RAW this invention, consists in conveying an elec* electrodes are connected u tric current through the soap solution, in form of lather or of a liquid bath, with which the raw silk is tolbetreated, whereby the durfi tion of the treatment-is materially shortene a Example. Two electrodes of a material, which is not affected by the soap lather and which is a conductor of electricity, are arranged in a suitable apparatus for the treatment of'raw silk by means of sea lather in accordance with the process descri ed in my United States Letters Patent No. 8-t8,60 .dated March 26th 1907, the wells of the apparatus not being conductors of electricity, and the said electrodes being arranged at opposite sides of the apparatus, and in such a manner that they extend through the whole depth of the soap lather, but do not come into contact with the silk to be treated. These p in an electric circuit so that the density of the current which circulates between them is from to 2 amperes and over per square decimeter of electrode surface, while the tension of the current varlesin accordance with the distance separating the. said electrodes. For a distance of 44 centimeters the tension would be, for example, 120 volts, The electric current which circulates through the soap lather and eventually also through the soap .solution beneath the same considerably increases the action of the said lather so that the time requisite forsoftening or dissoh' the gum my matter (sericin) is materi y diminished. The result ofthis shortening of Specification of Letters Patent. Application filed July 6, 1907. Serial No. 882,538.

Patented Aug. 4, 1908.

the duration of the operation is that the silk; fibers acquire a higher degree of elasticity, greater strength and increased gloss b reason of the reduced time during whic it is maintained in contact with the soap lather.

The time requisite for the un of the rawsilk is l kewise reduc when the electric current is employed in the usual process forthe treatment of the silk, wherein the raw silk is subjected to theaction of a soap. solution inform of aliquid bath. Inthis case, two electrodes, which are unaffected by the soap bath, are arranged 'at op osite ends of p.

vat of wood or other materia which is not a conductor of electricity, in such a manner that they'extend from the to to the bottom of the soap solution containe' in the vat and are connected up in an electric circuit, in

such a way that the current flowing through the latter circulates through the soap solu tion during the treatment, the silk being treated in the usual way during this operation,

that is to say, being moved in the bath. In

'either case, that is to say, whet-her the process is carried out by means of a son bath or by so'a lather, the c-onductibility 0 the bath or of t e lather may be increased by a small addition of sodium phosphate or sodium acetate.

T'Vhat I claim is:

The described improvement in the ungunh ming of raw silk consisting in passing an electric current through the soa solution with which the silk is treatedwhi e the said silkis 80 in contactwith the said soap solution for the a purpose of reducing the duration of the operation and of obtaining a silk fiber which. possesses more gloss, strength and elasticity than hitherto. v

In witness whereof I have hereunto signed my name this 22 day of June 1907, in the presence of two subscribing witnesses.

. PE'l ER SCHMID. Witnesses:

Geo. Grrronn, QAMAND Rrrrsn. 

